Marine vessels are subject to overall bending loads during seawater exposure due to waves acting on the ship hull, as described in a publication entitled "Cumulative Lifetime Loadings For Naval Ships", distributed Nov. 15-20, 1998 in Anaheim, Calif. at the 1998 exhibition symposium of the International Mechanical Engineering Congress, relating to "Unsteady Fluid Loading On Naval Structures". A copy of such publication is submitted herewith as an Appendix and its content is incorporated herein by reference.
Bending loads imposed on marine vessels as a result of seawater activity, have been classified under two principal components acting on the hull structure, consisting of a low frequency wave-induced loading component and a high-frequency slam loading component. Bending loads are currently predicted on the basis of the low frequency component using a simplified "static balance" type of computational method predicated on the assumption of a static equilibrium position for the ship hull on a hypothetical stationary ocean wave. However, such static balance methods for predicting bending loads actually experienced by a ship hull during its lifetime, has a serious shortcoming in failing to take into account various factors, including current statistical information on the sea utilized for low frequency bending calculation and the expected operating life of the ship, as well as the impact of seawater or ocean waves on the hull, referred to as high frequency slam loading. It is therefore an important object of the present invention to address the foregoing referred to shortcomings involving incorrect predictions in bending load magnitudes that a ship may actually experience during its lifetime.